Lighting system



Oct. 7, 1941. w. J. RADY LIGHTING SYSTEM 2 Sheets-Sheet 1 Filed March 25, 1958 Cui g h.

mmw

. NE'Z mm m Whm w T MW INVENTOR WILUAM J. RADY (D wm 4 ATTORNEYd I tions of operation. Fig. 9 isa fragmentary wiring diagram show- Patented Oct. 7, 1941 UNITED STATES PATENT OFFICE LIGHTING SYSTEM William .1. Italy. Anderson, Inde assi nmto General Motors Corporation, Detroit, Micln, a corporation of Delaware Appl cation March as, 1938, s mi No. 197,980

- 2 Claims. (01. 111411) This invention relates to electric lighting circuits for automotive vehicles and particularly to the type of lighting circuit which provides for automobile parking, city driving, country driving and country passing.

It is an object of the present invention to provide a simple and effective device for indicating when a lamp filament has burned out. I aim to accomplish this object by the use of a single relay switch having two windings which are differentially related. When the differential in amperes exceeds a certain amount, the relay switch will close to energize a signal, preferably a visible signal, such as a lamp on the instrument board. I provide a main lighting circuit control switch which is so constructed and connected in the circuit that, regardless of whether the switch is set for city driving, country driving, or country passing, the ampere differential of'the two relay windings is below the-amperes required to close indicated by the fine lines and the leg A circuit and its branch circuits are indicated in heavy black lines. The leg B circuit and its branches are indicated by the fine parallel lines.

It will be noted that leg A includes an electromagnetwinding a of relay R and leg 13 includes an electromagnet winding b surrounding a magnetizable core 0 attached to the frame 11 which supports a hinged armature e spring urged into contact open position as shown. Armature e carries a'contact f engageable with a contact a connected by'wire h with an'indicating lamp L grounded at m. The armature e is connected with the battery either through the A circuit or the B circuit.

The main switch 8 has stationary contacts 2|, 22, 23, 24, 25, 26, 21, 28 and 29 and movable contacts which are in the form of triangular Figs. 1 to 4 inclusive, are similar wiring diagrams showing one form of embodiment of the present invention in four different conditions of operation.

Figs. 5 to 8 inclusive, are similar wiring plates 20, 3| and 32. The movable contact plates 30, 31 and 32 are mechanically connected together, but not electrically, sothat they can be operated by a push pull rod.

"The parking position of switch 8 is shown in Fig. 1 in which it will be noted that contact Ill does not connect leg A with anything. Contact 3| connects leg A through contact 23 with contacts 21 and 22. Contact 32, though it connects contacts 24 and 28, does not complete any circuit. Only the head lamp filaments 2-2 andthe tail lamps 1 are blu'ning, hence the legend,

' "Park A (2,1)"

appearing at the bottom of this figure.

diagrams of another form of the present invention showing the system in four different condi:

ing a. modification of the diagram Fig.'5.

Fig. 10 is a simplified circuit diagram illustrating the features of the invention.

Referring to Fig. 1, H1- represents the right head lamp and Hi the left head lamp. Lamp Hz Fig. 2 shows the city driving posliton of the switch. Leg A, that is, the heavy black line, is

connected with head lamp filament 8 through contact 2|, bridged by contact with contact 26. Leg A is connected with tail lamp 1 through has filaments #2, #4 and #6 and lamp 1-11 has 7 filaments #2, #5,-a'nd #8. The #2 filaments are for city parking, the #5 and #4 filaments are for country driving, and the #6 and #8 filaments are for city driving. The #6 filament is used also for country passing. Lamp #1 at the bottom current is the storage battery 20 which is grounded, as are all of the lamp filaments. The lighting current is distributed from the battery through two main branches or circuits called, respectively, leg A and leg B. In the diagrams Figs. 1, 2, 3 and 4, the non-operative circuits are of the diagram is the tail lamp. The source of i contact 23 bridged by contact 3| with contact 21. Leg B is connected with head lamp filament 8 by contact 32 which bridges contacts 28 and 29. For city driving, head lamp filament 8 and I and tail lamp filaments 1 are connected with the bat-- tery. Leg A delivers current to filaments 6 and 1 and'leg B to filament 8. Hence, the following legend appears below the diagram Fig. 2:

"City driving Fig. 3 shows the switch S in condition for country driving. Leg A is connected with the tail lamp 1 and with head lamp filament 4 through contact "which bridges contacts 23, 24 and 21.. The circuit to filament 4 is through a dimmer switch D8, which is not a resistance dimmer switch, but is a switch which shifts a connection from a central contact either to the fila- Country passing ment 4, which is the main driving filament for the right-hand head lamp, or to the filament 6 which is a depressed beam filament for the right- 8 A e hand head lamp. The switch DS is conveniently mounted on the floor board of the vehicle and Lam! Limp is operated by foot pressure operating through a mechanism involving a ratchet and pawl type f3 5 of movement. Leg B is connected with head lamp filament 5 by contact 32 which bridges 1o -5 contacts and 29. Therefore, for country driving, leg A supplies current to the tail lamp I Dill. 1.31 am and to the main filament 4 of lamp Hr and leg EXAMPLE No 2 B supplies current to the main filament 5 of lamp HI. Hence, the following legend appear-s 15 Same-as Example No. 1 except at 5.5 volts.

below Fig.3: City driving Country driving A (4,1) A Le B B (5)" 2o 8 Fig. 4 shows the condition of the lighting sys- Lamp Lamp tem for country-passing. There has been no change in switch S; it is in the same position as g -12 3 for country driving, but the dimmer switch DS has been moved to transfer the connection in the 25 I leg A circuit from filament 4 to the depressed beam filament 6. Hence there appears below this Difl. .sa diagram the following legend: countmdmnng Country passing an A (B, 'I) Leg A Leg B B (5)" Y Y In order to aid in the understanding that this Lamp mp distribution of lighting current through the legs A and B for the various positions of the switches 23 5 which control the lighting circuits gives a diflerential below the operating differential of the relay when all of the selected filaments are burning and gives 'a diiferential between legs A and mm B which is above the operating diflferential of 40 Country passing the relay when one of the selected filaments burns out, the following five examples are given Leg A Le B of, a lighting circuit constructed and operated 8 according to the diagrams Figs. 1 to 4. Lamp Amp Lamp Am EXAMPLE No. 1

Showing differential current in the coils of the g 1 5 relay at 8 volts, using 32 C. P. filaments #4 and 3 23 no #5 and 21 C. P. filaments #6 and #8 with all selected filaments forming: Bin 97 City driving Exam No. 3

LagA m B Difierential current with various filaments out at 5.5 volts:

Lamp i M p Amp. y d iving i 8262i 8 3.25 Bout Bout 8.89' 3.25 LogA Lean LegA LegB mm M .53 no 3.23 '0 country driving 131112.11 piazza Leg A B Country driving Lamp Amp. Lamp Amp. Mint 4 bout 5 a 5 0.20 9 Legs LegB Le s LegB 5.84 no I .53 4.20 4.73 0

pm. .04 Difi. 3.01 pm. 4.73

ama 3 Country passing Country driving 50!! I A A ma 14A 1...; Lamp Amp. Lamp Amp.

Dlfi.3.67 Dimaas 4.83. 4.30 It will be noted from the foregoing examples Nos. 1, 2 and 3, that the largest difierential of mass amp.

current between the coils a and b o! the rela with all the filaments burning is 1.81 amperes as in country passing. The smallest differential with one filament out is 2.17 amperes as in city driving. The relay should be set at 1.75 amber-es to close the circuit oi the tell-tale lamp L when one of the selected filaments goes out.

Emmet: No. 4 showing diflerential current in the coils of the relay at 8 volts, which gives the maximum differential, using 32 C. P., filaments #4, #5, #6 and #8 with all selected filaments burning.

City driving LegA LegB Lamp Amp. Lamp Amp.

Dill. amp. Country driving LegA LegB Lamp Amp. Lamp Amp.

Difl .64 amp.

Country passing LegA LegB Lamp Amp. Lamp Amp.

min. amp. Exmu No. 5 Same as Example No. 4 except 5.5 volts:

City driving LegA LegB Lamp Amp. Lamp Amp.

Country passing LegA LegB Lamp Amp. Lamp Amp.

Dill. .53 amp.

From examples Nos. 4 and 5 it is obvious that, with filament I or 5 defective, there will be a diiiferential current between the relay windings oi 5.84 amp. at 8 volts and 4.83 amp. at 5.5 volts. With filaments 5 or 4 defective, there will be a minimum diilerential of 3.17 amperes. The relay may, here, be set to close at 3 amperes.

In the preceding examples no consideration has been given to the parking circuit because the current flowing through leg A when parking is below the current required to operate the relay.

In the circuit shown in Figs. 5, 6,.7 and 8, there is a head lamp Hr having a direct b'eam filament 4 and an auxiliary or depressed beam filament 6.

The head lamp H1 has a main or direct beam filamentl and the auxiliary or depressed beam filament l0. Instead of providing the headlamps with parking filaments 2, as shown in Figs. 1 to 4,

the system of Figs. 5 to 8 provides tender or marker lights 2. As in the Figs. 1 to 4, there is the 'tail lamp 1. The switch S has stationary contacts 4|, 42, 43, 44, 45, 45, 41, 48, 49, 50 and 5i and movable contacts 52, 53 and 54. Contacts 45 and 49 are not connected together on the inside of the switch but there is a strap 55 on the back of the switch or terminal block which connects contacts 48 and 49. Contact 48' is connected with contact 45 on the back oithe switch by a strap 55.

Fig. 5 shows the parking position of switch S. It will be apparent that leg A supplies current only to the marker lamps 2 and the tail lamp I. Leg B supplies no current. Hence there appears below this diagram the legend,

Park I In the city driving position of the switch .3 contact 52 bridges contacts 4|, 42 and 41. Contact 53 does not connect contact 43 with anything, although the lower point of contact 53 appears under the strap 55 which, as stated before, is not on the inside of the switch but is only onthe outside. marker lamps 2 and to filament 6 of head lamp Hr. Leg B is connected by contact 54 with contacts 50 and 45. Contact 45 is connected by strap 56 with contact 49 connected by strap 55 with lamp 1. Contact 50' is connected with filament l5. Hence leg B feeds current to tail lamp Thus leg A feeds current to 4t 2,257,856 Ti and filament it of head lamp H1. Thereiore, 3 Country passing below the diagram Fig. 6 appears the legend,

City driving LegA LegB A (6, 2) E (7, 10) 5 Lamp Amp. Lamp Amp. Fig. 7 shows the country driving position of switch S in which contact 52 makes no circuit 3 22 6 connection with the battery. Contact 53 bridges 7 M contacts M and 89. Contact 59 is connected l 5 14 5.29 by strap with tail lamp E. Contact 48 is conenected with filament a. Therefore, leg A sup= pm 06 plies current to tail lamp 5 and to filament l of head lamp Hr- Switch contact 54 connects con- EXAM? 7 ta ts' it a d H e leg B supp s urre t same as Example No. S at 5.5 volts: to filament 5 of head lamp H1. Hence, there appears below the diagram Fig. 7 the legend, City driving Countr rivin a (a, 7 d g a: B (5) Lamp Amp. Lamp Amp. Fig. 8 shows the country passingvcondition ct the circuit. The switch 8 is not changed from its o 2.10 10 2.10 position shown in Fig. 7, but the dimmer switch 2 1 DS is changed in order to divert current flowing 3.73 3.23 in lee A from the filament t to the filament t3 and; also to the marker lamps 2 through a con- 131f -5O nection. established by the contact 5% which bridges contacts and 52. Therefore, leg A supplies current to lamps t5, 2, and '11 and leg B supplies current to lamp Hence, below the die. s sh Country driving gram 8 appears the legend,

Country passing Lamp Lamp A (6,2 7) a (5)" 3 1??? 6 In order to understand how the system il1us 4.78 4.20 trated in Figs. 5, 6 and 7 effects distribution of current such that, in all driving positions of the D151 main switch S, the differential in legs A and B AA) is less than that required to operate the relay R when all the selected filaments are burning and Country passing is sufficient to operate the relay R in case one c I Less of the selected. filaments burns out, Examples Nos. 6, 7 and 8 are given. Lamp Lamp EXAMPLE No. 6 6 M0 5 LL20 Showing difierential current in the coils of the t :23 relay at 8 volts, using 32 C. P., filaments #4 and. 4 4 20 v #5, and 21 .C. P. filaments #Sand #10 with all selected filaments forming. Djfi 06 city driving I EXAMPLE No. 8

v Differential current with various filaments out Leg! LegB at 5.5 volts: Lamp Amp. Lamp Amp. Czty dnmng o a. 25 10 a. 25 I 6 out 10 out 2 1.25 7 .04

1.50 as; LegA LegB LegA LegB Dmnm 1.03 3.23 3.73 .53

Country driving I Dill. 2.20 Difi. 2.2a Leg A LegB Country driving Lamp Amp. Lamp Amp. out Bout 5. 5 5.20 7 LcgA LegB LcgALegB Difl. .64 out. as? our. m

' misses the operation oi the lighting system shown in Figs. 5, 6, 'l and 8 with the switch S substituted,

the following Examples Nos. 9, 10 and 11 are given:

- relay at 8-volts, which gives maximum difierential, when using all 32 C. P. .head lamp filaments with all selected filaments burning.

City driving 'IMA LegB Lamp Amp. Lamp Ampa see mam Country passing Lamp Amp.

' qua at 5.5 volts:

i y drivina 6 out 10 out LegA MB Dig. 2.77

Country passing, Country driving n I A I B Bout Bout v Lamp Amp. Lamp Amp. us ess ms ms 4 u) s as: us '4. us 0 7 ass no mass; mum. Dun From the foregoing examplesNos. 6, ,7 and 8, c mpaging it will be noted that the maximum difi'erential betweentheeoilswithalloithelampsbumingis In a .64 ampere as in country driving and that the I ,minimum'difierential with one light out is 2.20 m Amp. amperes as in city driving. Relay B should in this case be set to close at 1.75 amperes. u, 5 If the requirements 01' the system shown in s 1.20 Figs. 5, 8, 'l and 8 were for 32 C. P. filaments for r all of the head lamp filaments #4, #5, #6 and 7-0 am #IO, then the construction of the switch 8 could be much simplified. Fig. 9 shows the modifica- 1311-1-89 tion S of switch 8, which couldslzae made if all my, N 10 oi the head lamp filaments were C. P. .It will F I be noted that the contact is omitted entirely Same as Example No. 9 except at 5.5 volts.

and also the Jumper it. The contacts 4| and 40 Cm! driving are merged into one long contact instead oi there being two contacts insulated from eachother on LegA Le 1;

the inside oi the switch but connected on the back 0! the switc by a jumper strap 55. Oth- Lamp Amp. Lamp Amp. erwise the const tion or the switch is the same. Therefore, when this switch is in parking pom- 2 J ms -10 sec -tion, as shown, leg A supplies current to lamps I g 1% and I. and leg Bis not energized In the city a 0 driving position, leg A supplies current to filaments #3, #8 and #7, and leg B supplies current mm 1 M to filament #10. This is diflerent from the city 6 Mr H driving condition of the circuit according to Fig. 40 v v 6. The country driving and country passing pov sitions oi the 'switch 8' set up the same circuits MA MB asin Figs. 7 and 8, respectively, that is, when i switch 8' is in country driving position, leg A supplies current to filaments #4 and #7 and leg. 4 o 5 B to filament #5; and, when switch 8' is in the 1 country passing position, leg A supplies current ass 4.so to filaments #6, #2 and #7 and leg B supplies current to filament #5. In order to understand ms. .53

c Country driving From the foregoing Examples Nos. 9, 10 and 11,

it will be observed that the largest differential between the coils with all the lamps burning is 1.89 amperes as in No. 9, and that the lowest differential with any filament burned out is 2.77 amperes as found in city driving and country passing. The relay could be adjusted to close at 2.25 amperes, thus assuring its being open with all filaments burning and closed when any filament is defective. I

With the system according to Figs. 5 to 8 but modified according to Fig. 9 and employing '32 C.-P.,main filaments #4 and #5, and 21 C. P. depressed beam filaments #6 and it"), it has been found that the relay will not give an indication in case the filament #6 burns out, withswitch S in the city driving position, because the differential between the coils is lower' than that required to operate the relay under other conditions of operation of the circuit, such as, when the switch S is either in the country driving position or in the country passing position. It is, therefore, necessary to use the switch S as shown in Figs. 5 to 8 setting of the relay R is higher than with the system' shown in the other figures, the current setting being as high as 3 amperes when 32 C. P. filaments are used in all of the driving filaments of the lamps. It will also be noted that the number of turns in the coil b in leg B could be increased with respect to the number of turns in the coil a of leg A. Then a somewhat larger differential in ampere turns can be obtained to take care of the worst condition of ampere differential between the condition with all the lights burning, and the condition with one light defective.

From the foregoing description of the construction and mode of operation of various lighting systems embodying the present invention, it is apparent that the invention contemplates the use of a main current distributing switch to which current from the battery is fed through two legs A and B, each leg including one of two differentially related magnet windings of a tell-tale relay magnet core. The main distributing switch is required to divide up the current flow between the legs A and B in such manner that, for all driving positions of the switch S, the differential in the legs A and B with all selected, filaments burning is less than that required to operate the relay R, butthat when an one of the selected filaments burns out, the differential will be greater than that necessary to operate the relay R, whereby the relay R will be conditioned for operation 5 to connect the tell-taleslgnal lamp with the battery whenever the filament of a; lamp burns out, the main switch being in a driving light position. a While the embodiment of the present invention as herein disclosed, constitutes a preferred form, 10 it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows: 1. A lighting system for automotive vehicles comprising a current source, a plurality of filament circuits including head lamp main filaments, of a. designated current draft, head lamp auxiliary filaments of a different current draft and a 'tail lamp filament, a signal lamp, a relay for connecting the signal lamp with the current source and provided with differential windings each connectible with separate filaments and which, if in approximate balance, maintains the signal lamp circuit open, and which, if out of balance by a certain amount, will close the signal lamp circuit, switching means for selectively connecting the current source with selected combinations of filaments and, for arranging the selected combinations in two circuits from the current source, each circuit from the current source including a winding of the relay and a head lamp filament, said tail lamp filament, when the selected combination of head lamp'filaments includes filaments of different current draft,.being connected with the relay winding joining the fila- 4g ments of a designated candle power, and head lamp auxiliary filaments of a-difierent candle power, each arranged in pairs, and a tail lamp filament, all connectible with the source in selected groups, a signal lamp for indicating the 5 failure, of a filament in a selected group, a relay afor connecting the signal lamp with the current source and provided with a pair of differential windings, switching means for selectively connecting like and unlike filaments of each head lamp, and the tail lamp filament as a group said tail lamp filament when unlike head lampv filaments are selected, being connected with the relay winding in the branch including the head lamp filament of lesser candle power, the two branches from the switching means when con-' nected with the current source requiring different amounts of current, and the respective relay windings, both branches connected with the current source effecting a differential of magnetism in the relay less than a predetermined value required to operate the relay in connecting the signal lamp to the current source the arrangement of each relay winding with the selected filaments in series therewith being such that failure of one of the filaments so connected will increase the differential to such an extent as to exceed the predetermined value required to operate the relay, and thereby cause the relay to connect the signal lamp withthe source. 7

WILLIAM J. RADY. 

